| 1. |
- Ambrosi, Aurelie, et al.
(författare)
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Development of heart block in children of SSA/SSB-autoantibody-positive women is associated with maternal age and displays a season-of-birth pattern
- 2012
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Ingår i: Annals of the Rheumatic Diseases. - London : BMJ Publishing Group. - 0003-4967 .- 1468-2060. ; 71:3, s. 334-340
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Tidskriftsartikel (refereegranskat)abstract
- Objective Congenital heart block may develop in the fetuses of Ro/SSA-positive and La/SSB-positive mothers. Recurrence rates of only 10-20% despite persisting maternal antibodies indicate that additional factors are critical for the establishment of heart block. The authors investigated the influence of other maternal and fetal factors on heart block development in a Swedish population-based cohort. less thanbrgreater than less thanbrgreater thanMethods The influence of fetal gender, maternal age, parity and time of birth on heart block development was analysed in 145 families, including Ro/La-positive (n=190) and Ro/La-negative (n=165) pregnancies. less thanbrgreater than less thanbrgreater thanResults There was a recurrence rate of 12.1% in Ro/La-positive women, and no recurrence in Ro/La-negative women. Fetal gender and parity did not influence the development of heart block in either group. Maternal age in Ro/La-positive pregnancies with a child affected by heart block was, however, significantly higher than in pregnancies resulting in babies without heart block (pandlt;0.05). Seasonal timing of pregnancy influenced the outcome. Gestational susceptibility weeks 18-24 occurring during January-March correlated with a higher proportion of children with heart block and lower vitamin D levels during the same period in a representative sample of Swedish women and a corresponding higher proportion of children with heart block born in the summer (pandlt;0.02). Maternal age or seasonal timing of pregnancy did not affect the outcome in Ro/La-negative pregnancies. less thanbrgreater than less thanbrgreater thanConclusion This study identifies maternal age and seasonal timing of pregnancy as novel risk factors for heart block development in children of Ro/La-positive women. These observations may be useful for counselling when pregnancy is considered.
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| 2. |
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| 3. |
- Bai, Lucy, et al.
(författare)
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Clinical assessment of breast symmetry and aesthetic outcome : Can 3D imaging be the gold standard?
- 2023
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Ingår i: Journal of Plastic Surgery and Hand Surgery. - 2000-656X .- 2000-6764. ; 57:1-6, s. 145-152
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Tidskriftsartikel (refereegranskat)abstract
- There is a lack of an accurate standardised objective method to assess aesthetic outcome after breast surgery. In this methodological study, we investigated the intra- and inter-observer reproducibility of breast symmetry and volume assessed using three-dimensional surface imaging (3D-SI), evaluated the reproducibility depending on imaging posture, and proposed a new combined volume-shape-symmetry (VSS) parameter. Images were acquired using the VECTRA XT 3D imaging system, and analysed by two observers using VECTRA Analysis Module. Breast symmetry was measured through the root mean square distance. All women had undergone bilateral risk-reducing mastectomy and immediate breast reconstruction. The reproducibility and correlations of breast symmetry and volume measurements were compared using Bland-Altman's plots and tested with Spearman's rank correlation coefficient. 3D surface images of 58 women were analysed (348 symmetry measurements, 696 volume measurements). The intra-observer reproducibility of breast symmetry measurements was substantial-excellent, the inter-observer reproducibility was substantial, and the inter-posture reproducibility was substantial. For measurements of breast volumes, the intra-observer reproducibility was excellent, the inter-observer reproducibility was moderate-substantial, and the inter-posture reproducibility was substantial-excellent. The intra-observer reproducibility of VSSVSS was excellent while the inter-observer reproducibility was substantial for both observers, independent of posture. There were no statistically strong correlations between breast symmetry and volume differences. The intra-observer reproducibility was found to be substantial-excellent for several 3D-SI measurements independent of imaging posture. However, the inter-observer reproducibility was lower than the intra-observer reproducibility, indicating that 3D-SI in its present form is not a great assessment for symmetry.
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| 4. |
- Bai, Lucy, et al.
(författare)
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Patient-reported outcomes and 3-dimensional surface imaging after risk-reducing mastectomy and immediate breast reconstruction
- 2021
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Ingår i: Plastic and Reconstructive Surgery - Global Open. - 2169-7574. ; 9:5
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Tidskriftsartikel (refereegranskat)abstract
- The cosmetic results after risk-reducing mastectomy (RRM) and immediate breast reconstruction (IBR) are intended to be long-lasting. Long-term follow-up of the cosmetic outcome can be evaluated subjectively by the women themselves through patient-reported outcome measures such as questionnaires, or by using data from three-dimensional surface imaging (3D-SI) to calculate the volume, shape, and symmetry of the reconstructed breasts as a more objective cosmetic evaluation. The study aim was to evaluate the correspondence between patient-reported measures and 3D-SI measurements.Methods: Questionnaires (EORTC QLQ-BRECON23 and BIS) were sent to women on average 13 [7-20] years after RRM and IBR. Items were preselected for comparison with 3D measurements of women imaged using the VECTRA XT 3D-imaging system at the long-term follow-up.Results: Questionnaire responses and 3D images of 58 women, 36 without and 22 with previous breast cancer (where 15 also received radiotherapy) before RRM and IBR, were analyzed. Median age at follow-up was 57 [41-73] years. Patient-reported satisfaction with the cosmetic outcome was positive for both groups. 3D measurements indicated more symmetrical cosmetic results for women without previous breast cancer. No statistically significant associations between patient-reported satisfaction and 3D measurements were found.Conclusions: Satisfaction with the long-term cosmetic outcome after RRM and IBR was, in general, positive when evaluated by the women. 3D-SI could be used as a more objective approach to assess the cosmetic outcome in terms of volume and shape-symmetry; however, it does not directly translate to the patient-reported satisfaction.
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| 5. |
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| 6. |
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| 7. |
- Bryhn, Andreas, et al.
(författare)
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Fisk- och skaldjursbestånd i hav och sötvatten 2019 : Resursöversikt
- 2020
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Fisken i havet är en resurs som rör sig fritt över nationella gränser. EU har därför en gemensam fiskeripolitik (GFP). Många arter som är viktiga för Sverige regleras inte i GFP och förvaltas därför nationellt.Denna rapport syftar till att:beskriva utvecklingen av fiskeripolitikenförklara den nuvarande politikens mål och regelverk och dess relation till mål och regler på miljöområdetförklara politikens nationella genomförande och det nationella handlingsutrymmetexemplifiera hur Havs- och vattenmyndigheten arbetat med att reglera fisket.
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| 8. |
- Bryhn, Andreas, et al.
(författare)
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Fisk- och skaldjursbestånd i hav och sötvatten 2020 : Resursöversikt
- 2021
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- I rapporten kan du ta del av bedömningen som görs av situationen för bestånd som regleras inom ramen för EU:s gemensamma fiskeripolitik (GFP). Bedömningarna baseras på det forskningssamarbete och den rådgivning som sker inom det Internationella Havsforskningsrådet (ICES). Totalt redovisas underlag och råd för 48 fisk- och skaldjursarter.De bestånd som förvaltas nationellt baseras på de biologiska underlagen, och rådgivningen i huvudsak på den forskning och övervakning samt analys som bedrivs av Institutionen för akvatiska resurser vid Sveriges lantbruksuniversitet (SLU Aqua) samt yrkesfiskets rapportering.
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| 9. |
- Dahllöf, Lisbeth, et al.
(författare)
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Energi-och miljömärkning av lätta fordon : Frågebatteri för produktions- och skrotningsfaserna
- 2022
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- I denna rapport analyseras olika möjligheter och metoder för att deklarera miljö- och energiaspekter som uppstår vid tillverkning och skrotning av personbilar och lätta lastbilar. Uppdraget har beställts av Energimyndigheten som har fått i uppdrag av Regeringen att ta fram ett förslag till en metod för energi- och miljömärkning av lätta fordon på den svenska marknaden.Dagens regelverk inom EU ställer inga krav på att tillverkaren behöver ange energiåtgång och miljöpåverkan vid tillverkning och skrotning av ett fordon. Det finns därför inga officiella uppgifter som skulle kunna användas i en miljömärkning. Man är i stället hänvisad till att antingen använda generella data från livscykelanalyser, eller begära in frivilliga uppgifter från tillverkaren. IVL Svenska Miljöinstitutet har tagit fram tänkbara alternativ till att energi- och miljömärka tillverkningsfasen inklusive återvinning och skrotning. Rekommendationen är att en sådan miljö-märkning införs i flera steg och eftersom det saknas officiella uppgifter om enskilda fordon behöver metodiken utprovas gradvis.I rapporten presenteras tre olika förslag på upplägg med varierande detaljnivå. I alternativ 1 föreslås att man tar fram ett schablonvärde vardera för energiåtgång och växthusgaser för ett urval av sex typer av personbilar respektive lätta lastbilar. Värdet ska motsvara den genomsnittliga energiåtgången och de genomsnittliga utsläppen av växthusgaser på global nivå vid tillverkning, skrotning och återvinning av de olika typer av fordon som idag förekommer på marknaden. Alternativ 2 utgår från samma metod som alternativ 1 men schablonvärden för energiåtgång och växthusgaser anges istället som en funktion av fordonets tjänstevikt. Alternativ 3 utgår från också från schablonvärden för energiåtgång och växthusgaser men siffrorna kompletteras med tillverkaruppgifter om växthusgaser från tillverkningen av laddbara batterier. För att få en mer heltäckande bild föreslås ett komplement till alternativen ovan att tillverkaren även erbjuds att frivilligt besvara ett antal frågor som belyser fler miljöaspekter.
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| 10. |
- Fredrik, Öhberg, et al.
(författare)
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Gait analysis using a portable motion sensor system : measurements in subjects with hip implant as compared with healthy controls
- 2013
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Ingår i: Gait & Posture. - : Elsevier BV. - 0966-6362 .- 1879-2219. ; 38:suppl 1, s. 99-100
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Tidskriftsartikel (refereegranskat)abstract
- Introduction: There is an increase of age related diseases such as hip joint arthritis, something that is often treated with hip replacement surgery. The aim of this study was to quantify movement function and its effect on quality of life in persons treated with hip implant, in comparison to matched asymptomatic controls.Patients/Materials and Methods: This is an ongoing study, and so far, 2 asymptomatic subjects (CTRL, age 50 ± 13 years, BMI 23 ± 2), and 4 subjects with hip implant (HIP, age 51 ± 15 years, BMI 25 ± 3), have been analyzed. The HIP group received their implant 2.6 ± 1.1 years ago and finished their rehabilitation 1.6 ± 1.1 years ago. Hip dysfunction and Osteoarthritis Outcome Score (HOOS) was used to assess the subject's hip function and its associated problems. A functional calibration (flexion/abduction movements) was done and each subject then performed 5 repetitions of gait (approx. 25 left/right gait cycles). Movement was registered with a custom-developed portable motion sensor system, where each sensor consisted of a tri-axial accelerometer and gyroscope. Sensors were placed on pelvis and each thigh and shank. Further calculations were done in MATLAB (v7.12 R2011a, Mathworks). Cosine rotation matrices were extracted by functional sensor-to- segment-calibration and sensor fusion [1], and hip and knee angles were obtained as Euler angles.Results: Preliminary results indicated larger range in hip rotation and smaller range of knee flexion during gait in HIP group than in the CTRL group (Fig. 1). HOOS profile (Fig. 2) indicated that hip function during sports (SP) and the general quality of life (QOL) were lower in the HIP group.Fig. 1. Mean and SD of hip and knee angle over 15 gait cycles in one HIP subject (blue) as compared with the CTRL group (black). (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)Figure optionsFig. 2. HOOS profiles in HIP (blue square) and CTRL group (black). (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)Figure optionsDiscussion and conclusions: Motion patterns during gait seemed to be negatively affected in subjects with hip implant, even after the rehabilitation program was completed and even though the HOOS profiles indicated a relative good hip function.Reference[1]J. Favre, B.M. Jolles, O. Siegrist, K. AminianQuaternion-based fusion of gyroscopes and accelerometers to improve 3D angle measurement
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| 11. |
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| 12. |
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| 13. |
- Holgersson, Georg, et al.
(författare)
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The value of induction chemotherapy for survival in patients with non-small cell lung cancer treated with radiotherapy.
- 2012
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Ingår i: Anticancer research. - : The International Institute of Anticancer Research. - 1791-7530 .- 0250-7005. ; 32:4, s. 1339-46
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Tidskriftsartikel (refereegranskat)abstract
- AIM: The aim of the present study was to retrospectively investigate the impact of induction chemotherapy on treatment outcome in patients treated with curatively intended radiotherapy for non-small cell lung cancer (NSCLC). PATIENTS AND METHODS: Patients with a diagnosed NSCLC that have been subjected to curatively intended irradiation (≥50 Gy) and treated in an oncology department in Sweden during the years 1990-2000 were included in the study. Operated patients and patients having received concomitant chemotherapy were excluded. The included patients were localised by a manual search of all the oncology departments' medical records and radiation charts. RESULTS: Patients treated with induction chemotherapy (n=79) had a significantly better overall survival compared with patients treated with radiotherapy alone (p=0.0097) in a univariate Cox regression analysis. A platinum/taxane combination produced the greatest survival benefit; hazard ratio=0.49 (95% confidence interval=0.31 to 0.75). CONCLUSION: We found that patients treated with induction chemotherapy in addition to radiotherapy for NSCLC have a better overall survival than patients treated with radiotherapy alone and that the best results are achieved using a platinum/taxane combination.
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| 14. |
- Johansson, Ulf, et al.
(författare)
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Är anpassning av skogsskötseln nödvändigt i dagsläget för att minska skogsskador i ett förändrat klimat?
- 2012
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- En klimatförändring kommer att ändra förutsättningarna för de skogliga ekosystemen, vilketkommer sannolikt att kräva förändrade skogsbruks- och skötselmetoder. I denna rapport har vianalyserat tänkbara strategier för skogsbruket och sätta in dem i ett vidare perspektiv. Ensådan analys måste naturligtvis göras med stor ödmjukhet, eftersom kunskapsläget om vilkaeffekterna kan tänkas bli är dåligt och osäkerheterna kring alla relevanta prognoser är mycketstora.I den första delen av rapporten analyserar vi konsekvenserna av olika skogsskötselalternativpå beståndsnivå: (i) övergång till ett skogsbruk utan gallringar och med omloppstider kortareän de som idag tillämpas, (ii) en successiv övergång till ett lövskogsskogsbruk genom att efterslutavverkning alltid föryngra med löv var det andra alternativet och (iii) övergång tillhögproduktiva exotiska trädslag. De olika alternativen analyserades utifrån en beskrivenklimatförändring och utvärderades i termer av virkesproduktion, ekonomi och skaderisker.I den andra delen av rapporten försöker vi generalisera diskussionen till en regional nivå ochundersöka om slutsatserna blir annorlunda i denna skala. Skogliga analyser på beståndsnivåblir gärna endimensionella, då en funktion eller ett värde analyseras i taget (produktion,ekonomin, rekreation, biodiversitet etc). Tidsperspektivet blir ofta syntetiskt behandlat genomexempelvis val av diskonteringsfaktor i en nuvärdeskalkyl. Skogen som system tillhandahållersamtidigt en mängd varor, tjänster och andra värden. Då det är kombinationen av en mängdbestånd som utgör detta system krävs analyser på systemnivå för att skapa en helhetsbild.Vår förhoppning är att denna rapport leder till ökad kunskap och förståelse för de olikakomplexa samband och avvägningar som det svenska skogsbruket kommer att möta. Ett storttack riktas till forskningsprogrammen Mistra-SWECIA och Future Forests som har finansieratdetta projekt.
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| 15. |
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| 16. |
- Larsson, Mats-Ola, et al.
(författare)
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Bilanvändning och parkering : Rekommendationer till arbetsgivare
- 2022
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Denna PM är en del av projektet ”Klimatsmarta tjänste- och arbetsresor” som har undersökt resandet hos organisationerna Västra Götalandsregionen, Länsstyrelsen, Göteborgs Universitet och Chalmers. Erfarenheter från studien har sammanställts till generella råd om arbetsgivares möjligheter att använda hyrbilar och poolbilar i verksamheten och att tillämpa miljöstyrande riktlinjer för parkering för att minska klimatbelastning från tjänsteresandet.Råden handlar bl.a. om att kartlägga möjligheterna att ersätta resor med privat bil med hyr- och poolbilar och att ställa miljö- och trafiksäkerhetskrav på sådana bilar. Arbetsgivare kan också utforma ersättningsnivåer och riktlinjer på ett sätt som minimerar användningen av privat bil till tjänsteresor. För parkering rekommenderas marknadsmässig prissättning, inga rabatter och system som kräver löpande betalning hellre än att erbjuda årskort eller månadskort för parkering
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| 17. |
- Lundström, Filip, 1984-, et al.
(författare)
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A validation study of data in the National Tonsil Surgery Register in Sweden : high agreement with medical records ensures that data can be used to monitor clinical practices and outcomes
- 2022
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Ingår i: BMC Medical Research Methodology. - : BioMed Central. - 1471-2288. ; 22:1
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Tidskriftsartikel (refereegranskat)abstract
- Background: The ambition of the National Tonsil Surgery Register in Sweden (NTSRS) is to improve otorhinolaryngological care by monitoring trends in the clinical practices, complications, and outcomes of tonsil surgery. The NTSRS collects data from both surgeons and patients and provides the participating clinics with daily updated data on a publicly available website. On the website, national and local results can be compared and monitored. The use of NTSRS data necessitates that the data is valid, but the NTSRS has not yet been validated. With approximately half of the registered patients responding to the postoperative questionnaires, an analysis of responders and non-responders is also necessary. The aim of this study was to assess the criterion validity of NTSRS data. Another aim was to compare the characteristics and rates of complications between postoperative questionnaire responders and non-responders.Methods: Data in the NTSRS were compared with data in electronic medical records. The 200 most recent surger-ies, up to 31 Dec 2019, in each of 11 surgical units were included. Criterion validity was analysed in terms of observed agreement, Cohens kappa, Gwet’s AC1, and positive and negative agreement. The sign test was used to analyse systematic differences between the NTSRS and the medical records. Comparisons of rates between groups were made with Fisher’s exact test, the chi-square test, and Fisher’s non-parametric permutation test.Results: A total of 1991 registrations were included in the study. All variables showed very high observed agreement ranging from 0.91 to 1.00, and all variables had AC1 values corresponding to almost perfect agreement. The analysis of questionnaire responders and non-responders showed no statistically significant differences regarding age, indication, or type of surgery. The proportion of women was higher in the responder group. The rate of reoperation due to bleeding was higher in the responder group, but there were no differences regarding other complications.Conclusions: The results of this study show that data in the NTSRS have criterion validity. The NTSRS is thus well suited for monitoring the clinical practices and outcomes of tonsil surgery. The quality of the data also implies that the registry can be used in both clinical improvement projects and research.
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| 18. |
- Lundström, Filip, et al.
(författare)
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Practice, complications and outcome in Swedish tonsil surgery 2009-2018. An observational longitudinal national cohort study
- 2020
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Ingår i: Acta Oto-Laryngologica. - : Informa UK Limited. - 0001-6489 .- 1651-2251. ; 140:7, s. 589-596
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Tidskriftsartikel (refereegranskat)abstract
- Background: To assure a high quality in tonsil surgery, it is necessary to monitor trends in clinical practice, complications and outcome. Aims/objectives: To describe rates and trends regarding indications, methods, techniques, complications, and outcome of tonsil surgery. Material and method: 98 979 surgeries from the National Tonsil Surgery Register 2009-2018. Groups were categorised by indication and method. Results: The proportion of patients undergoing tonsillotomy with adenoidectomy due to obstruction-snoring (mean age 5.3 y.) increased from 2009-2018. Hot tonsillectomy, but not tonsillotomy, techniques were related to a higher risk for postoperative bleeding. The use of cold techniques increased for all types of surgeries. The rates of patients reporting contact due to postoperative pain were associated with indication and method, with the lowest rate reported for tonsillotomy (4.5% in 2018) and the highest for tonsillectomy (34.5% in 2009). The rate of patients reporting that their symptoms were gone 6 months after surgery decreased. Conclusions and significance: All hot tonsillectomy techniques should be avoided as they are related to a higher risk for postoperative bleeding. The high rate of postoperative contacts due to pain after tonsillectomy indicates a need for improvement in pain management. The declining rates of symptom relief must be investigated further.
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| 19. |
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| 20. |
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| 21. |
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| 22. |
- Stenlund, Tobias, 1975-, et al.
(författare)
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Adaptation of postural reactions in seated positions and influence of head posture when exposed to a single sideway perturbation : relevance for driving on irregular terrain
- 2016
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Ingår i: Journal of Novel Physiotherapy and Physical Rehabilitation. - : Peertechz Publications Private Limited. - 2455-5487. ; 3:1, s. 022-029
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Tidskriftsartikel (refereegranskat)abstract
- Background and objectives: Mechanical perturbations in seated positions caused by driving on irregular terrain destabilize the driver which, combined with the drivers’ posture, may cause musculoskeletal disorders. The aim of this study was to investigate adaptation and the effect of different head postures on seated postural reactions caused by perturbations. Materials and Methods: Twenty healthy male participants, aged 18-43 years, were tested on a movable platform delivering 15 sideways perturbations (peak acceleration 13.3 m/s2) while the participants held their head in a neutral or a laterally flexed posture. Surface electromyography (EMG) signals were recorded bilaterally in upper neck, trapezius, erector spinae and external oblique, while kinematics were recorded with inertial sensors for the head, trunk and pelvis. EMG amplitudes, muscle onset latencies and angular displacements in the frontal plane were analyzed. Results: In the neutral position, the EMG amplitudes and neck angular displacements significantly decreased by 0.2% and more than 1.6° respectively after repeated perturbations. Muscle onset latencies remained unchanged. During lateral flexion of the head, the EMG amplitudes decreased by 0.5% but the muscular onset latencies increased by more than 9 ms. Conclusion: The developed neuromuscular strategy seem to prefer a reduced EMG amplitude. The modest size of the postural reactions during the conditions presented here do not by themselves explain the musculoskeletal disorders found in drivers.
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| 23. |
- Stenlund, Tobias, et al.
(författare)
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Assessing postural load among drivers exposed to shock-type whole-body vibration using inertial measurements units : Results from measurements on standardized courses
- 2019
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Konferensbidrag (refereegranskat)abstract
- Background: Lower back and neck pain is common among persons who drive vehicles in their profession. The vehicle occupants are exposed to whole-body vibration (WBV) that may include mechanical shocks which are believed to increase the likelihood of injury further. Mechanical shocks are especially generated when driving on rough terrain and may challenge drivers' postural equilibrium. Little is known about the contribution of postural load to injury risk and thus objective measurements are necessary.Purpose: The purpose of the study was to assess the feasibility of registering and analyzing seated postural load and shock-type WBV synchronously using inertial measurement units (IMUs) among drivers of forest machines during terrain-like conditions.Methods: Five male participants (18-34 years old) drove a forest machine 6 times over three different standardized steal obstacles along a gravel course using a predefined speed and posture. Participants then drove the same vehicle 3 times over natural obstacles along a terrain course using a self-selected speed and posture. Three IMUs were affixed along the spine (at S2, Th2 and C4) and one to the head of participants as well as one to the seat. Data from the IMUs regarding accelerations and orientation in sagittal, frontal and horizontal plane were then analyzed.Results: Postural load, expressed as the range of motions (ROMs) in the upper neck, lower neck, trunk and pelvis were less than 22° in all directions during maneuvers on the standardized course. The size of obstacle and the vehicle speed had significant effects on the ROMs. No significant differences between courses were evident regarding seat accelerations and angular velocities at the drivers head. The WBV analysis of the terrain course indicated that mechanical shocks were prevalent but exceeded the exposure action value for only one driver and not the exposure limit value according to health and safety requirements within the European Union (EU directive 2002/44/EC).Conclusion(s): IMUs may objectively be used to register and present seated postural load and shock-type WBV exposure synchronously when driving on terrain. There seems to be a low risk of injuries from mechanical shocks since the magnitude of postural load (ROMs) during tested conditions was not considered to increase injury risk even though vehicle speed and the size of obstacles had a significant effect.Implications: Postural load when driving a forest machine during terrain-like conditions appears low in this study but more long-term field measurements on more drivers are needed before definite conclusions can be made. IMUs are regarded as promising tools for registering and representing seated postural load and shock-type WBV exposure. Future development could provide drivers with feedback regarding potentially injurious postures and/or high shock-type WBV exposure.
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| 24. |
- Stenlund, Tobias, et al.
(författare)
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Double-sided Mechanical Shocks Provoke Larger Seated Postural Reactions Compared to Single-Sided Mechanical Shocks
- 2018
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Ingår i: Spine. - 0362-2436 .- 1528-1159. ; 43:8, s. E482-E487
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Tidskriftsartikel (refereegranskat)abstract
- STUDY DESIGN: Human volunteers were exposed experimentally to single-sided mechanical shocks (SSMS) and double-sided mechanical shocks (DSMS) while seated.OBJECTIVE: To describe and contrast seated postural reactions due to SSMS or DSMS in healthy male adults.SUMMARY OF BACKGROUND DATA: Mechanical shocks to the body, caused when driving on irregular terrain, are suggested to be hazardous to the spine and may be associated with the reported musculoskeletal pain of the back and neck among professional drivers. However, very little is known about the characteristics of seated postural reactions and the biomechanical effects caused by mechanical shocks.METHODS: Twenty healthy male subjects (18-43 years old) were exposed while seated to 5 SSMS and 15 DSMS in lateral directions. The second acceleration in the DSMS was in the opposite direction to the first acceleration and was either fast, medium or slow depending on the speed of direction change. Surface electromyography (EMG) was recorded in muscles of the upper neck, trapezius, erector spinae and external oblique while kinematics were recorded with inertial sensors placed at the neck, trunk and pelvis. Muscle activity was normalized to maximum voluntary contractions (MVC).RESULTS: The EMG amplitudes were significantly higher (0.6-1%; p < 0.001) for the fast DSMS compared to all other shocks. Range of motion (ROM) of the neck and trunk was greater during the DSMS compared to the SSMS. Evoked muscle activity was less than 2% MVC in the trapezius, less than 10% MVC in the erector spinae and upper neck while the activity exceeded 10% MVC in the external oblique muscles.CONCLUSION: Fast DSMS in lateral directions appear more demanding compared to SSMS, demonstrating augmented seated postural reactions. However, the present mechanical shocks employed did not seem to induce postural reactions with regard to ROM or muscle activity of a magnitude likely to cause musculoskeletal overload.LEVEL OF EVIDENCE: 4.
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| 25. |
- Stenlund, Tobias, 1975-, et al.
(författare)
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Greater seated postural reactions are provoked by double-sided compared to single-sided mechanical shocks
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Study design: Human volunteers were exposed experimentally to single-sided mechanical shocks (SSMS) and double-sided mechanical shocks (DSMS) while seated.Objective: To describe seated postural reactions due to SSMS and DSMS in healthy male adults.Summary of Background Data: Mechanical shocks, caused when driving on irregular terrain are suggested to be hazardous to the spine and may be associated with the reported musculoskeletal disorders of the back and neck among professional drivers.Methods: Twenty healthy male subjects (18-43 years old) were exposed while seated to 5 SSMS and 15 DSMS in lateral directions. The second acceleration in the DSMS was in the opposite direction to the first acceleration and divided into fast, medium and slow depending on the speed of direction change. Surface electromyography (EMG) was recorded in upper neck, trapezius, erector spinae and external oblique and kinematics were recorded with inertial sensors for the neck, trunk and pelvis. Muscle activity evoked by the shocks was normalized to maximum voluntary contractions (MVC).Results: The EMG amplitudes were significantly higher (0.6-1%; p<0.001) for the fast DSMS compared to all other shocks. Range of motions of the neck and trunk were greater from the DSMS compared to the SSMS. Muscle activity in the erector spinae and upper neck was sparse while the most intense muscle activity was found in the external obliques > 10% MVC, with elements of co-contraction.Conclusion: Fast DSMS in lateral directions appear more demanding compared to SSMS and increase seated postural reactions, especially activity in the external oblique muscles. Still, the extent of range of motions in the neck and trunk and muscle activities alone, do not suggest a high risk for musculoskeletal overload.
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| 26. |
- Stenlund, Tobias, et al.
(författare)
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Inter- and intra-tester reliability when measuring seated spinal postures with inertial sensors
- 2014
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Ingår i: International Journal of Industrial Ergonomics. - : Elsevier. - 0169-8141 .- 1872-8219. ; 44:5, s. 732-738
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Tidskriftsartikel (refereegranskat)abstract
- Prolonged awkward sitting postures may be associated with neck or back pain, but it is often unclear which specific postures cause most problems and which mechanisms that may underlie the pain. In order to increase the knowledge in this field, it seems crucial first of all to be able to analyse, in depth, different seated spinal postures. A problem is however the lack of reliable and direct measurement methods of the posture, especially for sitting. Recently developed systems with inertial sensor attached along the spine have potential for this purpose. The aim of the present study was therefore to test the reliability of using such a system to assess various seated postures. Inter- and intra-tester as well as intra-subject relative reliability was estimated with intra-class correlation coefficient (ICC). Absolute reliability was estimated with standard error of measurement (SEM) and smallest detectable change (SDC). Ten + ten healthy subjects and four testers participated. Three standardised unsupported seated postures (lumbar lordosis, lumbar kyphosis and neutral posture) and two standing postures (neutral and lumbar kyphosis) were evaluated using five sensors attached to the head, the thorax (high and low), the lumbar spine and the pelvis. The ICC for intra-tester reliability ranged from 0.37 to 0.90, SEM 2.5-12.0 degrees, and SDC 7.1-333 degrees where the largest measurement error was from the head. Intra-tester reliability was higher than inter-tester reliability but not as good as intra-subject reliability. The intra-tester absolute reliability was nevertheless not considered sufficient to distinguish smaller differences. The low reliability may depend on inertial sensor size and attachment but also on the tester's accuracy. This study shows that assessing unsupported seated spinal postures with inertial sensors could be performed with higher reliability if done by the same, rather than different, testers. Relevance to industry: Prolonged awkward seated postures at work may be associated with back and neck pain and should therefore be analysed. Inertial sensor units is a promising tool to measure spinal posture. Smaller sensors attached by one skilled tester directly onto the body will most likely improve assessment in the future. (C) 2014 Elsevier B.V. All rights reserved.
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| 27. |
- Stenlund, Tobias, et al.
(författare)
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Seated postural loads caused by shock-type whole-body vibration when driving over obstacles
- 2020
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Ingår i: International Journal of Forest Engineering. - : Taylor & Francis. - 1494-2119 .- 1913-2220. ; 31:3, s. 184-191
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Tidskriftsartikel (refereegranskat)abstract
- Operators of mobile machines within forestry work long hours in seated postures while being exposed to whole-body vibration (WBV) that is associated with pain in the lower back and neck. Still, little is known about the contribution from postural loads. In this study postural loads and shock-type WBV exposure on drivers operating a forwarder during terrain-like conditions was measured and quantified using inertial measurement units (IMUs). Five male drivers drove a forwarder repeatedly over standardized steel obstacles using a predefined speed and posture followed by driving over natural obstacles along a terrain course using a self-selected speed and posture. IMUs were affixed along the spine, on the back of the head of the driver and on the seat to detect orientation, velocity, and acceleration. The result shows that the methodology for measuring WBV and postural load with IMUs is feasible. Postural loads, expressed as range of motions (ROMs), when driving over a single standardized obstacle at a speed of 3.3 km/h were up to 21 degrees in the neck segments. Increasing vehicle speed and size of obstacles increased postural loads. The terrain course resulted in higher ROMs in all body segments compared to a standardized obstacle, a difference in sideway seat acceleration but no differences regarding angular velocities of the head. Mechanical shocks at the seat were prevalent but the action limit value was exceeded only for one driver. Postural loads remained small during all conditions indicating that the spine can remain stable during exposure to shock-type WBV of this nature.
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| 28. |
- Stenlund, Tobias, 1975-, et al.
(författare)
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Seated postural neck and trunk reactions to sideways perturbations with or without a cognitive task
- 2015
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Ingår i: Journal of Electromyography & Kinesiology. - : Elsevier. - 1050-6411 .- 1873-5711. ; 25:3, s. 548-556
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Tidskriftsartikel (refereegranskat)abstract
- Driving on irregular terrain will expose the driver to sideways mechanical shocks or perturbations that may cause musculoskeletal problems. How a cognitive task, imposed on the driver, affects seated postural reactions during perturbations is unknown. The aim of the present study was to investigate seated postural reactions in the neck and trunk among healthy adults exposed to sideways perturbations with or without a cognitive task. Twenty-three healthy male subjects aged 19-36 years, were seated on a chair mounted on a motion system and randomly exposed to 20 sideways perturbations (at two peak accelerations 5.1 or 13.2 m/s2) in two conditions: counting backwards or not. Kinematics were recorded for upper body segments using inertial measurement units attached to the body and electromyography (EMG) was recorded for four muscles bilaterally in the neck and trunk. Angular displacements (head, neck, trunk and pelvis) in the frontal plane, and EMG amplitude (normalised to maximum voluntary contractions, MVC) were analysed. The cognitive task provoked significantly larger angular displacements of the head, neck and trunk and significantly increased EMG mean amplitudes in the upper neck during deceleration, although 10% of MVC was never exceeded. A cognitive task seems to affect musculoskeletal reactions when exposed to sideways perturbations in a seated position.
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| 29. |
- Stenlund, Tobias, 1975-
(författare)
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Seated postural reactions to mechanical shocks : laboratory studies with relevance for risk assessment and prevention of musculoskeletal disorders among drivers
- 2016
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Professional drivers of off-road vehicles, driving on irregular terrain such as in forestry, agriculture and mining, are exposed to whole-body vibration and mechanical shocks. These driver groups have reported severe musculoskeletal problems in the spine, but the association to seated postural reactions is not fully understood. One assumption is that unexpected shocks may create excessive load on spinal joints. The driver’s posture and exposure to mechanical shocks are required to be included in work risk assessments, but muscle activity and body kinematics are not included. The overall aim of this thesis was to describe and analyse seated postural reactions to mechanical shocks and to evaluate measuring of seated postures with relevance for risk assessment and the prevention of musculoskeletal disorders among drivers.The thesis includes four studies, all laboratory-based using a repeated-measures design. Postural reactions were recorded from 23 (Paper I) and 20 (Paper II & III) young, healthy male participants who were seated on a movable platform. The platform delivered mechanical shocks with peak accelerations up to 14 m/s2 in lateral directions during different conditions. Furthermore, twenty participants (Paper IV) were tested by four testers for analysis of test-retest reliability within and between testers measuring seated postures. Kinematics were here detected by means of a motion analysis system (MoLabTM) and described for the spine as angular displacements or range of motion (ROM) using a three-segment model of neck, trunk and pelvis (Paper I–III) and as a more specific model (Paper IV). Surface electromyography (EMG) was recorded bilaterally on the following muscles; trapezius upper part, upper neck, erector spinae and external oblique (Paper I–III).The general findings show that EMG amplitudes normalised to maximum voluntary contractions (MVC) did not exceed 2% in the trapezius, 8% in the upper neck and erector spinae and 18% in the external oblique. The EMG amplitudes and the angular displacements in the neck were significantly reduced from the first compared to the fifth mechanical shock. Adding a cognitive task significantly increased angular displacements. The largest ROM with approximately 20° in each segment was found during a double-sided mechanical shock (shock that changes direction). The reliability within one tester measuring seated postures was mostly considered good and superior to the reliability between several testers, but still insensitive to changes of less than 10°.Exposure to single-sided or double-sided mechanical shocks with accelerations up to 14 m/s2 seem not to cause postural reactions to such an extent that overload of muscles or joint structures should be expected. There seems to be a quick adaptation that causes an improved readiness. The external obliques were most active when restoring equilibrium and seem important for stabilising the whole spinal column. Stability training, in order to improve neuromuscular control of the external obliques could, therefore, be a possible recommendation. The angular displacement in the neck increases if the subject solves a cognitive task of why such activities should be avoided when driving in difficult terrains. Since accurate descriptions of the spinal posture seems difficult even when advanced technical equipment is used, simpler models seem more appropriate. The results show that postural control is maintained even when exposed to considerable mechanical shocks. On the basis of these results, there is no need to change established risk assessment models.
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| 30. |
- Ståhlberg, Ola, et al.
(författare)
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Autism Spectrum Disorders and Coexisting Mental Health Problems
- 2015
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Ingår i: Autism Spectrum Disorders: Phenotypes, Mechanisms and Treatment (Eds). M Leboyer, & P Chaste.. - Basel : Karger. - 9783318026016 ; , s. 5-19
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- It is rule rather than an exception that mental disorders occur in complex and manifold forms, and a number of models have been proposed to explain this co-occurrence or co-‘morbidity’. Autism spectrum disorders (ASD, i.e. autistic disorder, Asperger syndrome, and pervasive developmental disorder – not otherwise specified) are no exemption. Here, the literature on ASD co-occurring with developmental disorders (such as ADHD), learning disorders, and problems that typically arise during childhood (e.g. oppositional defiant disorder, conduct disorder), and adulthood (e.g. anxiety, affective/mood disorders, and psychotic disorders) will be reviewed. The patterns of mental disorders co-occurring with ASD could not be summarized into any consistent and easy-to-interpret model of co-morbidity. Thus, research on ASD should consider and not rule out coexisting mental conditions (and include persons with complex problems in studies), clinical assessments, and evaluations. Ignoring the complexity of co-occurring conditions will have detrimental effects in research, counteracting our understanding of the etiology behind ASD and the development of evidence-based, comprehensive treatment strategies.
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| 31. |
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| 32. |
- Yao, Yiming, 1957, et al.
(författare)
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Microstructure and properties of Al2O3-3wt% TiO2 plasma sprayed coating affected by powder manufacturing methods
- 2011
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Ingår i: ECerS XII, 12th Conference of the European Ceramic Society, Stockholm Sweden, June 19-23 2011.
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Plasma sprayed Al2O3-TiO2 ceramic coatings are widely used as protective coatings for promoting component performance with respect to wear, corrosion, and thermal insulation. In addition, Al2O3-TiO2 is an interesting matrix material for thermally sprayed composite coatings owing to its excellent chemical stability and thermal properties. With regard to dispersion of additives, the improvement of the microstructure homogeneity of conventional thermally sprayed coatings becomes an important aspect of the materials design and manufacturing process. The current study is aiming at controlling the microstructure of plasma sprayed Al2O3-3 wt%TiO2 coatings in terms of developing the feedstock powder manufacturing method. Two Al2O3+3wt% TiO2 powders produced by freeze granulation and different thermal treatment processes were plasma sprayed. The resulting coatings were investigated on microstructure, porosity, phase content, microhardness and crack growth resistance. The phase transformations occurring during thermal spraying are different to the one observed in commercial Al2O3-3 wt%TiO2 powder manufactured with a cladding process. In contrast to the conventional lamellar structure, a high degree of mixing of Al2O3 and TiO2 in the granulated powders results in a more uniform microstructure. Compared with the coating made from the commercial Al2O3-3 wt%TiO2 powder, the improved microstructure leads to a substantial increase of the crack growth resistance parallel to the coating plane without critically deteriorating microhardness of the coatings.
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| 33. |
- Yao, Yiming, 1957, et al.
(författare)
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Microstructure of plasma sprayed Al2O3-3wt%TiO2 coating using freeze granulated powder
- 2016
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Ingår i: Journal of Materials Science and Chemical Engineering. - : Scientific Research Publishing, Inc.. - 2327-6045 .- 2327-6053. ; 4:7, s. 8-14
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Tidskriftsartikel (refereegranskat)abstract
- This study is aiming at controlling the microstructure of plasma sprayed Al2O3-TiO2 composite coatings using freeze granulated powders. As sprayed and sintered Al2O3+3wt%TiO2 powders were air plasma spayed with industry process parameters and compared with a commercial powder. The resulting coatings were investigated with respect to powder flowability, porosity and microstructure of the granules. The results showed that microstructure and melting fraction in the coatings could be tailored with the freeze granulation process and heat treatment conditions.
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